title: Trigeminocardiac reflex in neurosurgical practice: An observational prospective study.
abstract: BACKGROUND
  Considering wide variations regarding the incidence of trigeminocardiac reflex (TCR) during cranial neurosurgical procedures, and paucity of reliable data, we intended to design a prospective study to determine the incidence of TCR in patients undergoing standard general anesthesia for surgery of supra/infra-tentorial cranial and skull base lesions.
  
  
  METHODS
  A total of 190 consecutive patients candidate for elective surgery of supra-tentorial, infra-tentorial, and skull base lesions were enrolled. All the patients were operated in the neurosurgical operating room of a university-affiliated teaching hospital. All surgeries were performed using sufficient depth of anesthesia achieved by titration of propofol-alfentanil mixture, adjusted according to target Cerebral State Index (CSI) values (40-60). All episodes of bradycardia and hypotension indicating the occurrence of TCR during the surgery (sudden decrease of more than 20% from the previous level) were recorded.
  
  
  RESULTS
  Four patients, two female and two male, developed episodes of TCR during surgery (4/190; 2.1%). Three patients showed one episode of TCR just at the end of operation when the skin sutures were applied while CSI values were 70-77 and in the last case, when small tumor samples were taken from just beneath the lateral wall of the cavernous sinus TCR episode was seen while the CSI value was 51.
  
  
  CONCLUSIONS
  TCR is a rare phenomenon during brain surgeries when patient is anesthetized using standard techniques. Keeping the adequate depth of anesthesia using CSI monitoring method may be an advisable strategy during whole period of a neurosurgical procedure.
authors.affiliation: Department of Anesthesiology, Sina Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Farhad
authors.initials: F
authors.lastname: Etezadi
authors.forename: Amir Ali
authors.initials: AA
authors.lastname: Orandi
authors.forename: Amir Hosein
authors.initials: AH
authors.lastname: Orandi
authors.forename: Atabak
authors.initials: A
authors.lastname: Najafi
authors.forename: Abbas
authors.initials: A
authors.lastname: Amirjamshidi
authors.forename: Pejman
authors.initials: P
authors.lastname: Pourfakhr
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Khajavi
authors.forename: Kazem
authors.initials: K
authors.lastname: Abbassioun
keywords: Cavernous sinus; cerebral state index; depth of anesthesia; neurosurgery; skin suture; trigeminocardiac reflex